Added 4 solutions

varunu28 · varunu28 · commit 680588b4a01c · 2018-10-04T11:31:18.000-07:00
diff --git a/Easy/Maximum Distance in Arrays.java b/Easy/Maximum Distance in Arrays.java
@@ -0,0 +1,17 @@
+class Solution {
+    public static int maxDistance(List<List<Integer>> arrays) {
+        int min = arrays.get(0).get(0);
+        int max = arrays.get(0).get(arrays.get(0).size()-1);
+        int result = Integer.MIN_VALUE;
+
+        for (int i=1; i<arrays.size(); i++) {
+            result = Math.max(result, Math.abs(arrays.get(i).get(arrays.get(i).size()-1) - min));
+            result = Math.max(result, Math.abs(arrays.get(i).get(0) - max));
+
+            max = Math.max(max, arrays.get(i).get(arrays.get(i).size()-1));
+            min = Math.min(min, arrays.get(i).get(0));
+        }
+        
+        return result;
+    }
+}
diff --git a/Easy/Strobogrammatic Number.java b/Easy/Strobogrammatic Number.java
@@ -0,0 +1,26 @@
+class Solution {
+    public boolean isStrobogrammatic(String num) {
+        Set<String> set = new HashSet<>();
+        set.add("0");
+        set.add("1");
+        set.add("8");
+        set.add("00");
+        set.add("11");
+        set.add("88");
+        set.add("69");
+        set.add("96");
+                
+        int start = 0;
+        int end = num.length()-1;
+        
+        while (start <= end) {
+            if (!set.contains(num.charAt(start) + "" + num.charAt(end))) {
+                return false;
+            }
+            start++;
+            end--;
+        }
+        
+        return true;
+    }
+}
diff --git a/Easy/Valid Word Sequence.java b/Easy/Valid Word Sequence.java
@@ -0,0 +1,33 @@
+class Solution {
+    public boolean validWordSquare(List<String> words) {
+        List<String> vertical = getStrings(words);
+        
+        for (int i=0; i<words.size(); i++) {
+            if (!words.get(i).equals(vertical.get(i))) {
+                return false;
+            }
+        }
+        
+        return true;
+    }
+    
+    private List<String> getStrings(List<String> strings) {
+        List<String> list = new ArrayList<>();
+        
+        for (int i=0; i<strings.size(); i++) {
+            StringBuilder sb = new StringBuilder();
+            int j = 0;
+            while (j < strings.size()) {
+                if (i < strings.get(j).length()) {
+                    sb.append(strings.get(j).charAt(i));
+                }
+                
+                j++;
+            }
+
+            list.add(sb.toString());
+        }
+        
+        return list;
+    }
+}
diff --git a/Explore/Medium/Arrays and Strings/Missing Ranges.java b/Explore/Medium/Arrays and Strings/Missing Ranges.java
@@ -0,0 +1,109 @@
+class Solution {
+    public static List<String> findMissingRanges(int[] nums, int lower, int upper) {
+        List<String> list = new ArrayList<>();
+
+        if (nums.length == 0) {
+            list.add(getString(lower, upper));
+            return list;
+        }
+
+        List<String> range = getRange(nums);
+        int i = 0;
+
+        while (lower <= upper && i < range.size()) {
+            String s = range.get(i);
+            if (s.indexOf('>') != -1) {
+                int start = Integer.parseInt(s.split("->")[0]);
+                int end = Integer.parseInt(s.split("->")[1]);
+
+                if (lower != start) {
+                    list.add(getString(lower, start-1));
+                }
+
+                lower = end + 1;
+            }
+            else {
+                int num = Integer.parseInt(s);
+                if (lower != num) {
+                    list.add(getString(lower, num-1));
+                }
+
+                lower = num + 1;
+            }
+
+            i++;
+        }
+
+        String s = range.get(range.size()-1);
+        if (s.indexOf('>') != -1) {
+            int start = Integer.parseInt(s.split("->")[0]);
+            int end = Integer.parseInt(s.split("->")[1]);
+
+            if (end != upper) {
+                list.add(getString(end+1, upper));
+            }
+        }
+        else {
+            int num = Integer.parseInt(s);
+            if (upper != num) {
+                list.add(getString(num+1, upper));
+            }
+        }
+
+        return list;
+    }
+
+    private static List<String> getRange(int[] num) {
+
+        List<String> list = new ArrayList<>();
+        if (num.length == 0) {
+            return list;
+        }
+
+        int i = 1;
+        StringBuilder sb = new StringBuilder();
+        sb.append(num[0]);
+        int count = 1;
+
+        while (i<num.length) {
+            if (num[i] - num[i-1] == 1 || num[i] - num[i-1] == 0) {
+                count++;
+            }
+            else {
+                if (count > 1) {
+                    sb.append("->").append(num[i-1]);
+                    list.add(sb.toString());
+                }
+                else {
+                    list.add(sb.toString());
+                }
+
+                sb = new StringBuilder();
+                sb.append(num[i]);
+                count = 1;
+            }
+
+            i++;
+        }
+        
+        if (count > 1) {
+            sb.append("->").append(num[num.length-1]);
+        }
+
+        list.add(sb.toString());
+
+        return list;
+    }
+
+    private static String getString(int start, int end) {
+        StringBuilder sb = new StringBuilder();
+        if (start == end) {
+            sb.append(start);
+        }
+        else {
+            sb.append(start).append("->").append(end);
+        }
+
+        return sb.toString();
+    }
+}
